1. Field of the Disclosure
The present disclosure relates to an electrophoretic display device which displays an image with electrophoresis, and a manufacturing method thereof.
2. Discussion of the Related Art
Electrophoretic display (EPD) devices denote devices that display an image with electrophoresis in which colored charged particles move by an electric field given from the outside. Herein, electrophoresis denotes an electrophoretic motion when an electric field is applied to electrophoretic dispersion liquid that is formed by dispersing charged particles into liquid, the charged particles moves in the liquid by Coulomb force.
Such EPD devices have bistability, and thus can maintain the original image for a long time even when an applied voltage is removed. That is, since EPD devices maintain a constant screen for a long time even when a voltage is not continuously applied thereto, the EPD devices are suitable for an e-book field that does not require the quick change of a screen. Also, EPD devices are not dependent on a viewing angle unlike Liquid Crystal Displays (LCDs), and moreover, provide an image comfortable for eyes by the degree similar to papers.
An EPD device includes an electrophoretic film, a substrate, and a Protective Sheet (PS). The electrophoretic film is formed between the substrate and the protective sheet. A Thin Film Transistor (TFT) is formed at one surface of the substrate facing the electrophoretic film. The protective sheet is formed on the reverse of the substrate with respect to the electrophoretic film. That is, the electrophoretic film is formed on the substrate, and the protective film is formed on the electrophoretic film.
Herein, since the electrophoretic film is vulnerable to water in characteristic, the EPD device is deteriorated in performance when the electrophoretic film is stained with water, and thus, reliability for the quality of the EPD device is degraded. To prevent such limitations, technology for preventing water from penetrating into the electrophoretic film is required to be developed in EPD devices.